import json
import logging

import pytest
from pydantic import BaseModel

from mcp.server.fastmcp import Context, FastMCP
from mcp.server.fastmcp.exceptions import ToolError
from mcp.server.fastmcp.tools import ToolManager
from mcp.server.session import ServerSessionT
from mcp.shared.context import LifespanContextT
from mcp.types import ToolAnnotations


class TestAddTools:
    def test_basic_function(self):
        """Test registering and running a basic function."""

        def add(a: int, b: int) -> int:
            """Add two numbers."""
            return a + b

        manager = ToolManager()
        manager.add_tool(add)

        tool = manager.get_tool("add")
        assert tool is not None
        assert tool.name == "add"
        assert tool.description == "Add two numbers."
        assert tool.is_async is False
        assert tool.parameters["properties"]["a"]["type"] == "integer"
        assert tool.parameters["properties"]["b"]["type"] == "integer"

    @pytest.mark.anyio
    async def test_async_function(self):
        """Test registering and running an async function."""

        async def fetch_data(url: str) -> str:
            """Fetch data from URL."""
            return f"Data from {url}"

        manager = ToolManager()
        manager.add_tool(fetch_data)

        tool = manager.get_tool("fetch_data")
        assert tool is not None
        assert tool.name == "fetch_data"
        assert tool.description == "Fetch data from URL."
        assert tool.is_async is True
        assert tool.parameters["properties"]["url"]["type"] == "string"

    def test_pydantic_model_function(self):
        """Test registering a function that takes a Pydantic model."""

        class UserInput(BaseModel):
            name: str
            age: int

        def create_user(user: UserInput, flag: bool) -> dict:
            """Create a new user."""
            return {"id": 1, **user.model_dump()}

        manager = ToolManager()
        manager.add_tool(create_user)

        tool = manager.get_tool("create_user")
        assert tool is not None
        assert tool.name == "create_user"
        assert tool.description == "Create a new user."
        assert tool.is_async is False
        assert "name" in tool.parameters["$defs"]["UserInput"]["properties"]
        assert "age" in tool.parameters["$defs"]["UserInput"]["properties"]
        assert "flag" in tool.parameters["properties"]

    def test_add_invalid_tool(self):
        manager = ToolManager()
        with pytest.raises(AttributeError):
            manager.add_tool(1)  # type: ignore

    def test_add_lambda(self):
        manager = ToolManager()
        tool = manager.add_tool(lambda x: x, name="my_tool")
        assert tool.name == "my_tool"

    def test_add_lambda_with_no_name(self):
        manager = ToolManager()
        with pytest.raises(
            ValueError, match="You must provide a name for lambda functions"
        ):
            manager.add_tool(lambda x: x)

    def test_warn_on_duplicate_tools(self, caplog):
        """Test warning on duplicate tools."""

        def f(x: int) -> int:
            return x

        manager = ToolManager()
        manager.add_tool(f)
        with caplog.at_level(logging.WARNING):
            manager.add_tool(f)
            assert "Tool already exists: f" in caplog.text

    def test_disable_warn_on_duplicate_tools(self, caplog):
        """Test disabling warning on duplicate tools."""

        def f(x: int) -> int:
            return x

        manager = ToolManager()
        manager.add_tool(f)
        manager.warn_on_duplicate_tools = False
        with caplog.at_level(logging.WARNING):
            manager.add_tool(f)
            assert "Tool already exists: f" not in caplog.text


class TestCallTools:
    @pytest.mark.anyio
    async def test_call_tool(self):
        def add(a: int, b: int) -> int:
            """Add two numbers."""
            return a + b

        manager = ToolManager()
        manager.add_tool(add)
        result = await manager.call_tool("add", {"a": 1, "b": 2})
        assert result == 3

    @pytest.mark.anyio
    async def test_call_async_tool(self):
        async def double(n: int) -> int:
            """Double a number."""
            return n * 2

        manager = ToolManager()
        manager.add_tool(double)
        result = await manager.call_tool("double", {"n": 5})
        assert result == 10

    @pytest.mark.anyio
    async def test_call_tool_with_default_args(self):
        def add(a: int, b: int = 1) -> int:
            """Add two numbers."""
            return a + b

        manager = ToolManager()
        manager.add_tool(add)
        result = await manager.call_tool("add", {"a": 1})
        assert result == 2

    @pytest.mark.anyio
    async def test_call_tool_with_missing_args(self):
        def add(a: int, b: int) -> int:
            """Add two numbers."""
            return a + b

        manager = ToolManager()
        manager.add_tool(add)
        with pytest.raises(ToolError):
            await manager.call_tool("add", {"a": 1})

    @pytest.mark.anyio
    async def test_call_unknown_tool(self):
        manager = ToolManager()
        with pytest.raises(ToolError):
            await manager.call_tool("unknown", {"a": 1})

    @pytest.mark.anyio
    async def test_call_tool_with_list_int_input(self):
        def sum_vals(vals: list[int]) -> int:
            return sum(vals)

        manager = ToolManager()
        manager.add_tool(sum_vals)
        # Try both with plain list and with JSON list
        result = await manager.call_tool("sum_vals", {"vals": "[1, 2, 3]"})
        assert result == 6
        result = await manager.call_tool("sum_vals", {"vals": [1, 2, 3]})
        assert result == 6

    @pytest.mark.anyio
    async def test_call_tool_with_list_str_or_str_input(self):
        def concat_strs(vals: list[str] | str) -> str:
            return vals if isinstance(vals, str) else "".join(vals)

        manager = ToolManager()
        manager.add_tool(concat_strs)
        # Try both with plain python object and with JSON list
        result = await manager.call_tool("concat_strs", {"vals": ["a", "b", "c"]})
        assert result == "abc"
        result = await manager.call_tool("concat_strs", {"vals": '["a", "b", "c"]'})
        assert result == "abc"
        result = await manager.call_tool("concat_strs", {"vals": "a"})
        assert result == "a"
        result = await manager.call_tool("concat_strs", {"vals": '"a"'})
        assert result == '"a"'

    @pytest.mark.anyio
    async def test_call_tool_with_complex_model(self):
        class MyShrimpTank(BaseModel):
            class Shrimp(BaseModel):
                name: str

            shrimp: list[Shrimp]
            x: None

        def name_shrimp(tank: MyShrimpTank, ctx: Context) -> list[str]:
            return [x.name for x in tank.shrimp]

        manager = ToolManager()
        manager.add_tool(name_shrimp)
        result = await manager.call_tool(
            "name_shrimp",
            {"tank": {"x": None, "shrimp": [{"name": "rex"}, {"name": "gertrude"}]}},
        )
        assert result == ["rex", "gertrude"]
        result = await manager.call_tool(
            "name_shrimp",
            {"tank": '{"x": null, "shrimp": [{"name": "rex"}, {"name": "gertrude"}]}'},
        )
        assert result == ["rex", "gertrude"]


class TestToolSchema:
    @pytest.mark.anyio
    async def test_context_arg_excluded_from_schema(self):
        def something(a: int, ctx: Context) -> int:
            return a

        manager = ToolManager()
        tool = manager.add_tool(something)
        assert "ctx" not in json.dumps(tool.parameters)
        assert "Context" not in json.dumps(tool.parameters)
        assert "ctx" not in tool.fn_metadata.arg_model.model_fields


class TestContextHandling:
    """Test context handling in the tool manager."""

    def test_context_parameter_detection(self):
        """Test that context parameters are properly detected in
        Tool.from_function()."""

        def tool_with_context(x: int, ctx: Context) -> str:
            return str(x)

        manager = ToolManager()
        tool = manager.add_tool(tool_with_context)
        assert tool.context_kwarg == "ctx"

        def tool_without_context(x: int) -> str:
            return str(x)

        tool = manager.add_tool(tool_without_context)
        assert tool.context_kwarg is None

        def tool_with_parametrized_context(
            x: int, ctx: Context[ServerSessionT, LifespanContextT]
        ) -> str:
            return str(x)

        tool = manager.add_tool(tool_with_parametrized_context)
        assert tool.context_kwarg == "ctx"

    @pytest.mark.anyio
    async def test_context_injection(self):
        """Test that context is properly injected during tool execution."""

        def tool_with_context(x: int, ctx: Context) -> str:
            assert isinstance(ctx, Context)
            return str(x)

        manager = ToolManager()
        manager.add_tool(tool_with_context)

        mcp = FastMCP()
        ctx = mcp.get_context()
        result = await manager.call_tool("tool_with_context", {"x": 42}, context=ctx)
        assert result == "42"

    @pytest.mark.anyio
    async def test_context_injection_async(self):
        """Test that context is properly injected in async tools."""

        async def async_tool(x: int, ctx: Context) -> str:
            assert isinstance(ctx, Context)
            return str(x)

        manager = ToolManager()
        manager.add_tool(async_tool)

        mcp = FastMCP()
        ctx = mcp.get_context()
        result = await manager.call_tool("async_tool", {"x": 42}, context=ctx)
        assert result == "42"

    @pytest.mark.anyio
    async def test_context_optional(self):
        """Test that context is optional when calling tools."""

        def tool_with_context(x: int, ctx: Context | None = None) -> str:
            return str(x)

        manager = ToolManager()
        manager.add_tool(tool_with_context)
        # Should not raise an error when context is not provided
        result = await manager.call_tool("tool_with_context", {"x": 42})
        assert result == "42"

    @pytest.mark.anyio
    async def test_context_error_handling(self):
        """Test error handling when context injection fails."""

        def tool_with_context(x: int, ctx: Context) -> str:
            raise ValueError("Test error")

        manager = ToolManager()
        manager.add_tool(tool_with_context)

        mcp = FastMCP()
        ctx = mcp.get_context()
        with pytest.raises(ToolError, match="Error executing tool tool_with_context"):
            await manager.call_tool("tool_with_context", {"x": 42}, context=ctx)


class TestToolAnnotations:
    def test_tool_annotations(self):
        """Test that tool annotations are correctly added to tools."""

        def read_data(path: str) -> str:
            """Read data from a file."""
            return f"Data from {path}"

        annotations = ToolAnnotations(
            title="File Reader",
            readOnlyHint=True,
            openWorldHint=False,
        )

        manager = ToolManager()
        tool = manager.add_tool(read_data, annotations=annotations)

        assert tool.annotations is not None
        assert tool.annotations.title == "File Reader"
        assert tool.annotations.readOnlyHint is True
        assert tool.annotations.openWorldHint is False

    @pytest.mark.anyio
    async def test_tool_annotations_in_fastmcp(self):
        """Test that tool annotations are included in MCPTool conversion."""

        app = FastMCP()

        @app.tool(annotations=ToolAnnotations(title="Echo Tool", readOnlyHint=True))
        def echo(message: str) -> str:
            """Echo a message back."""
            return message

        tools = await app.list_tools()
        assert len(tools) == 1
        assert tools[0].annotations is not None
        assert tools[0].annotations.title == "Echo Tool"
        assert tools[0].annotations.readOnlyHint is True
